Analysis and research prospect of lightning-induced voltages in overhead transmission lines

The evaluation of electromagnetic transients in overhead power lines due to nearby lightning return strokes requires accurate models for the calculation of both the incident lightning electromagnetic pulse (LEMP) and the effects of coupling of this field to the overhead lines. Meanwhile, the influence of ground resistivity and the number of line conductors should be considered on analyzing the distribution characteristic of lightning-induced voltage. This paper reviews the most significant results obtained by well-known experts concerning the calculation of lightning-induced voltages, and points out some problems to be taken into account from now on. First, the theoretical basis and computation model for the calculation of lightning electromagnetic and lightning-induced voltage in overhead power lines is illustrated; then, combining with the results of domestic and foreign scholars, the distribution characteristic and influencing factors of lightning-induced transient in overhead power lines are analyzed; finally, some problems which can be studied are proposed: 1) the influence of multi-coupling among the conductors on lightning-induced voltage, 2) model for lightning-induced voltage in overhead lines considering ground layered structure.